<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
</head>

<body>
    <script>
        for (; ;) {
            let count = prompt(`
            1.输入的是 + - * /计算两个数字的结果
            2.如果输入Q则是退出结束程序
            `)
            let num1 = +prompt('请您输入第一个数字')
            let num2 = +prompt('请您输入第二个数字')
            if (count == '+') {
                alert(`计算结果是${num1 + num2}`)
            } else if (count == '-') {
                alert(`计算结果是${num1 - num2}`)
            } else if (count == '*') {
                alert(`计算结果是${num1 * num2}`)
            } else if (count == '/') {
                alert(`计算结果是${num1 / num2}`)
            } else if (count == 'q') {
                alert('退出程序')
                break
            }


        }
    </script>

</body>

</html>